Whats the difference between a muscle and tendon?
A. Muscles are the contractile units that move our bones and thus move our bodies. Tendons are the portions of muscle that connect the muscle to the bones, so the unit looks like this: bone-tendon-muscle-tendon-bone. Each muscle has a responsibility of moving bones closer together when contracting, to provide movement or maintain posture. Muscles and tendons have relatively good blood flow and thus speedy healing, in contrast to ligaments. This is important to understand as the junction between muscle and tendon and tendon and bone are common areas of injury when something is causing extra strain and the unit has to give somewhere. You can think of the junctions as forming a seam. If your calf is chronically tight in the belly of the muscle, it may eventually pull enough to strain at the tendon. Much like if you are wearing a pair of pants that are too tight and stretch out past the point of resistance, the pants will most likely rip at the seam.
